title: The SAH Score: a comprehensive communication tool.
abstract: BACKGROUND
  The Hunt and Hess grade and World Federation of Neurological Surgeons (WFNS) scale are commonly used to predict mortality after aneurysmal subarachnoid hemorrhage (aSAH). Our objective was to improve the accuracy of mortality prediction compared with the aforementioned scales by creating the "SAH score."
  
  
  METHODS
  The aSAH database at our institution was analyzed for factors affecting in-hospital mortality using multiple logistic regression analysis. Scores were weighted based on relative risk of mortality after stratification of each of these variables. Glasgow Coma Scale (GCS) was subdivided into groups of 3-4 (score = 1), 5-8 (score = 2), 9-13 (score = 3), and 14-15 (score = 4). Age was categorized into 4 subgroups: 18-49 (score = 1), 50-69 (score = 2), 70-79 (score = 3), and 80 years or more (score = 4). Medical comorbidities were subdivided into none (score = 1), 1 (score = 2), or 2 or more (score = 3).
  
  
  RESULTS
  In total, 1134 patients were included; all-cause SAH hospital mortality was 18.3%. Admission GCS, age, and medical comorbidities significantly affected mortality after multivariate analysis (P < .05). Summated scores ranged from 0 to 8 with escalating mortality at higher scores (0 = 2%, 1 = 6%, 2 = 8%, 3 = 15%, 4 = 30%, 5 = 58%, 6 = 79%, 7 = 87%, and 8 = 100%). Positive predictive value (PPV) for scores in the range 7-8 was 88.5%, whereas 6-8 was 83%. Negative predictive value (NPV) was 94% for range 0-2 and 92% for 0-3. The area under the curve (AUC) for the SAH score was .821 (good accuracy), compared with the WFNS scale (AUC .777, fair accuracy) and the Hunt and Hess grade (AUC .771, fair accuracy).
  
  
  CONCLUSIONS
  The SAH score was found to be more accurate in predicting aSAH mortality compared with the Hunt and Hess grade and WFNS scale.
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Anesthesia Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: nnaval1@jhmi.edu.
authors.forename: Neeraj S
authors.initials: NS
authors.lastname: Naval
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Kowalski
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Tiffany R
authors.initials: TR
authors.lastname: Chang
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Filissa
authors.initials: F
authors.lastname: Caserta
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Anesthesia Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: J Ricardo
authors.initials: JR
authors.lastname: Carhuapoma
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Rafael J
authors.initials: RJ
authors.lastname: Tamargo
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D016009:Chi-Square Distribution; D015897:Comorbidity; D003661:Decision Support Techniques; D005260:Female; D015600:Glasgow Coma Scale; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis* / Q000401:mortality*; D055815:Young Adult
keywords: Subarachnoid hemorrhage; aneurysm; mortality; outcome; stroke